Risks to Health Among American Indian/Alaska Native High School Students in the United States

Introduction According to the World Health Organization, the 10 leading risk factor causes of death in high-income countries are tobacco use, high blood pressure, overweight and obesity, physical inactivity, high blood glucose, high cholesterol, low fruit and vegetable intake, urban air pollution, alcohol use, and occupational risks. We examined the prevalence of some of the leading risks to health among nationally representative samples of American Indian/Alaska Native (AI/AN) high school students and compared rates across racial/ethnic groups. Methods We combined data from the 2001, 2003, 2005, 2007, and 2009 national Youth Risk Behavior Survey. The survey is a biennial, self-administered, school-based survey of 9th- through 12th-grade students in the United States. Overall response rates for the surveys ranged from 63% to 72%. Of 73,183 participants, 952 were AI/AN students. Results For 7 of the 16 variables examined in this study, the prevalence among AI/AN high school students was higher than the prevalence among white high school students. For 1 variable (ate fruit and vegetables <5 times per day), the prevalence among AI/AN students was significantly lower than that among white students. The prevalence for the remaining 8 variables was similar among AI/AN students and white students. These findings also show differences in the prevalence of some behaviors among AI/AN, black, and Hispanic students. Conclusion These findings show the prevalence of some health risk behaviors was significantly higher among AI/AN high school students than among high school students in other racial/ethnic groups.


Introduction
American Indians and Alaska Natives (AI/ANs) are people who have origins in any of the original peoples of North America and who maintain cultural identification through tribal affiliation or community recognition (1). In the 2000 Census, AI/ANs comprised approximately 1.5% of the US population (2). Approximately 2.5 million people identified only American Indian or Alaska Native as their race, and an additional 1.6 million people reported American Indian and at least 1 other race (2). As of 2000, 33% of the AI/AN population was younger than 18 years old, compared with only 26% of the total US population (3). In the 2005-2006 school year, 644,000 AI/AN youth attended public schools (4). AI/ANs have higher rates of illness and death than do members of other US racial/ethnic groups (5)(6)(7)(8). For example, the prevalence of heart disease and diabetes is higher among AI/AN adults than among adults in any other racial/ethnic group (5,9), and rates of physical inactivity (5,9), obesity (5,9,10), and cigarette smoking (5,9,10) are higher than those among white adults. National (11)(12)(13)(14)(15)(16), regional (17,18), and local (19) data show that AI/AN youth are at greater risk for many health problems than their non-AI/AN peers. Previous studies of disparities in health risk between AI/AN youth and youth of other racial/ethnic groups have been limited by a lack of adequate national data (20,21) and have either examined a limited number of risk behaviors or been based on data from limited groups of AI/AN youth.
According to the World Health Organization (WHO), the 10 leading risk factor causes of death in high-income countries are are tobacco use, high blood pressure, overweight and obesity, physical inactivity, high blood glucose, high cholesterol, low fruit and vegetable intake, urban air pollution, alcohol use, and occupational risks (22). We examined the prevalence of some of the leading risks to health among a nationally representative sample of US high school students and identified differences in prevalence among AI/AN students and students of other racial/ethnic groups. We also examined differences in prevalence of those health risks by sex among AI/AN students. We did not impute values for missing data. For the survey years, school response rates ranged from 75% to 81%, student response rates ranged from 83% to 88%, overall response rates ranged from 63% to 72%, and sample sizes ranged from 13,601 to 16,410. We applied a weighting factor to each record to adjust for school and student nonresponse and oversampling of black and Hispanic students. Details of the YRBS sampling strategies and the psychometric properties of the YRBS questionnaire have been reported elsewhere (23,24).

Measures
The YRBS measures 6 categories of health risk behaviors: 1) behaviors that contribute to unintentional injuries and violence; 2) tobacco use; 3) alcohol and other drug use; 4) sexual behaviors that contribute to unintended pregnancy and sexually transmitted disease, including human immunodeficiency virus infection; 5) unhealthy dietary behaviors; and 6) physical inactivity. The YRBS also monitors rates of obesity and overweight on the basis of body mass index (BMI) estimates derived from students' selfreported height and weight. In this study, we focused on the prevalence of variables measured in the YRBS that are consistent with behaviors or conditions WHO cites as the leading health risks (22): cigarette and alcohol use, dietary behaviors, overweight and obesity, and physical inactivity.
We analyzed the data among 4 categories of self-identified race/ethnicity: 1) American Indian or Alaska Native, non-Hispanic (hereafter referred to as AI/AN); 2) white, non-Hispanic (hereafter referred to as white); 3) black, non-Hispanic (hereafter referred to as black); and 4) Hispanic or Latino ethnicity, irrespective of race (hereafter referred to as Hispanic). Students who identified their race as Asian, Native Hawaiian or other Pacific Islander or who selected more than 1 response to the race question were assigned to the "other" race/ethnicity category. Thus, students in the AI/AN race category were those who selected only American Indian or Alaska Native as their race. . Data from 1,098 students whose race/ethnicity was not indicated and from The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
5,001 students in the "other" racial/ethnic category were excluded from this analysis.

Analysis
To account for the complex sample design of the survey, we conducted all analyses on weighted data by using SUDAAN version 9.0.1 (Research Triangle Institute, Research Triangle Park, North Carolina). Because the sex and age distributions in the 4 racial/ethnic groups were similar, we used t tests to identify significant differences between prevalence estimates for AI/AN students and those for students of other racial/ethnic groups; t tests were also used to identify significant differences in prevalence estimates between AI/AN girls and AI/AN boys. We considered differences significant at P ≤ .05.

Cigarette and alcohol use
The prevalence of ever having smoked cigarettes and current cigarette use was higher among AI/AN students than students in any other racial/ethnic group ( Table  1). The prevalence of current frequent cigarette use was significantly higher among AI/AN students than among black and Hispanic students. The prevalence of each of the 3 alcohol use behaviors was higher among AI/AN students than among black students. The prevalence of current alcohol use and binge drinking was higher among AI/AN boys than AI/AN girls.

Dietary behaviors, obesity, and overweight
Although the prevalence of eating fruits and vegetables fewer than 5 times per day was higher among white students than among AI/AN students, the prevalence of overweight and obesity was higher among AI/AN students than among white students ( Table 2). The prevalence of drinking less than 3 glasses per day of milk was higher among black and Hispanic students than among AI/AN students. The prevalence of drinking less than 3 glasses per day of milk was higher among AI/AN girls than among AI/AN boys, whereas the prevalence of obesity was significantly higher among AI/AN boys than among AI/AN girls.

Physical activity
The prevalence of insufficient vigorous physical activity, watching television 3 or more hours per day, and not playing on at least 1 sports team (run by their school or community groups) was higher among AI/AN students than among white students ( Table 3). The prevalence of insufficient vigorous physical activity was higher among black students than among AI/AN students. The prevalence of insufficient moderate physical activity and watching television 3 or more hours per day was higher among both black and Hispanic students than among AI/AN students. The prevalence of not attending a physical education class was higher among AI/AN students than among Hispanic students. The prevalence of insufficient vigorous physical activity and not playing on at least 1 sports team was higher among AI/AN girls than among AI/AN boys. The prevalence of using computers 3 or more hours per day on an average school day was higher among AI/AN boys than among AI/AN girls.

Discussion
The findings of this analysis of YRBS data are generally consistent with national (11-16), regional (17,18), and local (19) data showing that AI/AN youth are at greater risk for many health problems than their non-AI/AN peers. This study fills a gap in the public health literature by providing nationally representative data of AI/AN, white, black, and Hispanic US high school students for various behaviors associated with the leading risks to health. For 7 of the 16 variables examined in this study, the prevalence among AI/AN high school students was higher than the prevalence among white high school students. The prevalence of all smoking and alcohol use variables was higher among AI/AN students than among black students, and the prevalence of all smoking variables and not attending physical education classes was higher among AI/AN students than among Hispanic students.
The causes of disparities in health outcomes are complex. Poor health outcomes are associated not only with engaging in health risk behaviors but also with poverty, unemployment, low education levels, and limited access to health care (26), all of which are common to many AI/AN communities (6,27,28). For example, an estimated 1 in 4 AI/AN adults lives in poverty compared with 1 in 11 white adults (5), and an estimated 16% of AI/AN children have no health insurance compared with 6% of white children (6).
The findings from this study suggest that public health action will be needed to reduce the prevalence of health Centers for Disease Control and Prevention • www.cdc.gov/pcd/issues/2011/jul/10_0193.htm The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
risk behaviors among AI/AN students. There are more than 560 federally recognized AI/AN tribes in the United States (4). The populations of these tribes range from fewer than 100 people to more than 750,000 people (20), and each tribe has its own distinct traditions and cultural heritage (17,27,29). Understanding the geographic, legal, and cultural context in which AI/AN people live is essential to addressing the elevated risk for many health problems found among AI/ANs: a one-size-fitsall approach would not be appropriate. Any school or community-based intervention should be conducted in partnership with AI/AN people to ensure that it is culturally relevant and includes development of the community capacity necessary to ensure the sustainability of the intervention (17,28).
In addition to the importance of culturally relevant interventions, for some behaviors, differences in the prevalence among boys and girls should be considered. For example, AI/AN girls drank less milk than AI/AN boys, and understanding this difference is important for ensuring adequate calcium intake among girls. Likewise, more AI/AN girls than boys had insufficient vigorous physical activity and did not play on a sports team. In contrast, the prevalence of binge drinking, computer use, and obesity was higher among AI/AN boys than girls.
The public health goals for the nation set in Healthy People 2010 address, in part, health risk behaviors among youth (26). The findings of this analysis of YRBS data show that AI/AN high school students (and students in other racial/ ethnic groups) have not yet met all of the target rates set in the Healthy People 2010 goals (Table 4). For example, the 2010 goal for current cigarette use is 16%, but 33.7% of AI/ AN students were current cigarette users. The prevalence among black students was 12.6%, lower than the Healthy People 2010 goal. The goal for binge drinking is 2.0%, but the prevalence of binge drinking among AI/AN students was 30.9% (nearly equivalent to the prevalence among white and Hispanic students). Similarly, the targets for vigorous physical activity (85% goal) and moderate physical activity (35% goal) have not been met, and rates among AI/AN students are 62.4% and 28.1%, respectively (ie, the inverses of insufficient vigorous and moderate physical activity reported in this study). A similar pattern is seen with other Healthy People 2010 goals for comparable risk behaviors measured in this study.
The findings of this study should be considered in the context of some limitations. First, because of the small number of students who identified their race as AI/AN, multiple years of YRBS data were combined to produce meaningful estimates of the prevalence of health risk behaviors. As a result, these prevalence estimates do not reflect any changes in the prevalence of these factors that may have occurred during the study period. In addition, because of the small number of AI/AN students in this study (even after combining 5 survey years of data), the 95% confidence intervals around the prevalence estimates for AI/AN students are wide. Second, because the YRBS combines American Indian and Alaska Native into a single race category, it was not possible to produce separate prevalence estimates for each group, and the results of at least 1 study showed notable differences in the prevalence of some risk behaviors among Alaska Native youth compared with American Indian youth not living in Alaska (17). Third, these data apply only to adolescents who attend high school and do not capture students who have dropped out of school. Nationwide, in 2007, of people aged 16 to 17 years, approximately 4% were not enrolled in a high school program and had not completed high school (30); the dropout rate among AI/AN youth is higher than among white and black youth, though lower than among Hispanic youth (4). Fourth, because the sampling frame did not include schools funded by the Bureau of Indian Education, the findings from this study are not generalizable to students served by those schools.
Assessment of the effectiveness of efforts to reduce or eliminate health disparities in the United States, a focus of Healthy People 2010 (26), requires ongoing analyses of high-quality surveillance data from minority populations. This analyses of YRBS data found that the prevalence of some health risk behaviors was significantly higher among AI/AN high school students than among high school students in other racial/ethnic groups, indicating that they are at higher risk for illness and premature death than students in other racial/ethnic groups. Public health efforts targeted to this population are essential to addressing these disparities.

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27-2b
Reduce tobacco use by adolescents (cigarettes in the past month by students in grades 9 through 12) 16%